The England stopper has had it made crystal clear to him that he has no future at Manchestr City after spening the 2016-17 campaign on loan in Italy with Serie A side Torino.
He had hoped there would be a way back into the City team but the capture of £35 million Ederson has put an end to that.
Hart will join the Hammers on loan with City part-funding his wages, but the Hammers will have an option to buy him outright.